Some properties of 3-hydroxy-3-methylglutaryl-coenzyme A synthase from ox liver.
نویسندگان
چکیده
Mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase (EC 4.1.3.5) was purified from ox liver, and obtained essentially free from 3-oxoacyl-CoA thiolases. The kinetic behaviour, like that of the synthases from chicken liver and yeast, is compatible with a reaction pathway involving condensation of an acetyl-enzyme with acetoacetyl-CoA. The Km for acetoacetyl-CoA, less than 1 micronM at pH 7.8, may possibly be low enough to permit rapid ketogenesis under physiological conditions without the need for a binary complex between the synthase and oxoacyl-CoA thiolase.
منابع مشابه
3-Hydroxy-3-methylglutaryl-coenzyme A synthase from ox liver. Purification, molecular and catalytic properties.
Mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase (EC 4.1.3.5) was purified to homogeneity from ox liver and obtained essentially free from acetoacetyl-CoA thiolase activity. The purification procedure included substrate elution from cellulose phosphate and chromatofocusing. The relative molecular mas was about 100 000 and S20,w0 was 6.36S. The enzyme appears to be a dimer of identical subu...
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عنوان ژورنال:
- The Biochemical journal
دوره 173 3 شماره
صفحات -
تاریخ انتشار 1978